This application is based on Patent application Ser. No. 2000-324531 filed Oct. 24, 2000 in Japan, the content of which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to an ink jet printing apparatus and a data processing method used for the same apparatus. Specifically, the present invention relates to an ink jet printing apparatus and a data processing method used for the apparatus, which, when an ink as a printing agent is ejected from a print head to form a print dot on a printing medium, in association with the operation, for example, before or after the operation, ejects a treatment liquid for insolubilizing or coagulating the color material such as a dyestuff or a pigment in the ink.
2. Description of the Prior Art
Heretofore, when performing printing on a printing medium such as plain paper using an ink jet printing method, there could occur a deterioration of print image quality due to an effect of blotting or the like of the ink. Further, there has also occurred a problem in that storage stability is not good because the print image is insufficient in water resistance.
With the aim of solving such problems, for example, Japanese Patent Application Laid-Open No. 58-128862 (1983) discloses a technology in which, before a print dot forming operation by ejection of ink as a printing agent for taking part in image formation, or after the print dot forming, a treatment liquid, which is also called a print improving liquid or a fixation improving liquid, or called processing liquid solely, having an effect of effectively fixing the ink is ejected to form a treatment liquid dot, so that these dots are overlapped on the printing medium. Further, Japanese Patent Application Laid-Open No. 64-63185 (1989) discloses a technology in which after a compound for insolubilizing a dyestuff in the ink is deposited to the printing medium, print ink is ejected to form a print dot. Still further, Japanese Patent Application Laid-Open No. 5-202328 (1993) discloses a method for ejecting a treatment liquid for fixing the print ink effectively to provide a water resistance prior to the print dot forming operation, a method for coating the treatment liquid onto the printing medium by a roller, and a method in which the print ink and the treatment liquid are mixed while they are being sprayed from sprayers to be deposited onto the printing medium so that water resistance and fixing of the print ink are improved.
However, all of the above prior art examples deposit the treatment liquid to all the forming positions of print dots on the printing medium, thereby consuming the treatment liquid in more than the necessary amount, and in particular in the case of color printing using multicolor inks, the prior art examples have a problem of color mixing due to an excessive amount of treatment liquid. Then, in Japanese Patent Application Laid-Open No. 8-52867 (1996), the present applicant proposed a technology capable of depositing the treatment liquid for improving the fixing and water resistance of the ink only in an appropriate amount to an optimum position so that the function of the treatment liquid could be fully provided.
However, presently, with increasing requirements for color prints or high-quality prints, the amount of data to be processed accordingly becomes large, and an increased printing speed is required; in view of efficiently forming the ejection data of the treatment liquid, the prior art still has problems to be solved.
It is therefore an object of the present invention to make the ejection data formation time of the appropriate treatment liquid nearly the same as the processing time when the data formation is not required, so that the printing speed can be increased.
In an aspect of the present invention, there is provided an ink jet printing apparatus using a print head on which ejection openings capable of forming print dots by ejecting inks on a printing medium are arranged, and a treatment liquid head on which ejection openings capable of forming treatment liquid dots by ejecting a treatment liquid for insolubilizing or coagulating a color material in the ink are arranged, the print head and the treatment liquid head being scanned relatively to the printing medium in a direction different from a direction of the arrangement, the apparatus comprising:
means for converting data continuing in a direction corresponding to the relative scanning as data for print dots to be formed on the printing medium into data in a direction corresponding to the arrangement direction of the ejection openings;
means for generating forming position information of the treatment liquid dots on the printing medium corresponding to the data for print dots; and
control means for processing the data conversion by the converting means and the generation of the treatment liquid dot forming position information by the generating means in a same sequence.
In another aspect of the present invention, there is provided an ejection data forming method for an ink jet printing apparatus using a print head on which ejection openings capable of forming print dots by ejecting inks on a printing medium are arranged, and a treatment liquid head on which ejection openings capable of forming treatment liquid dots by ejecting a treatment liquid for insolubilizing or coagulating a color material in the ink are arranged, the print head and the treatment liquid head being scanned relatively to the printing medium in a direction different from a direction of the arrangement, the method comprising the steps of:
converting data continuing in a direction corresponding to the relative scanning as data for print dots to be formed on the printing medium into data in a direction corresponding to the arrangement direction of the ejection openings;
generating forming position information of the treatment liquid dots on the printing medium corresponding to the data for print dots; and
controlling the data conversion by the converting step and the generation of the treatment liquid dot forming position information by the generating step to be processed in a same sequence.
In the apparatus or the ejection data forming method according to the present invention, the treatment liquid forming position information on the printing medium for ejecting the treatment liquid for insolubilizing or coagulating the color material in the ink, the respective print data is temporarily stored, for example, at the time of a conversion of raster data into column data (HV conversion). Treatment liquid forming-position processing is performed before rewriting of the HV conversion result, that is, the HV conversion processing and the treatment liquid forming position processing are carried out in the same processing, thereby providing high-speed processing.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.